Valve stem silencer



July 31, 1945. A. PASTORE 2,3804673 VALVE STEM SILENCER Filed Jan. 19,1944 awe/whoa jdam .Pasfore, v

abrqwws Patented July 31, 1945 UNITED STATES PATENT OFFlCE VALVE STEMSILENCER- Adam Pasture, Bridgeport, Conn.

Application January 19, 1944, Serial No. 518.895 4 Claims. o|.123-9o)This invention relates to exhaust or intake valves for internalcombustion engines, and has for the primary object the provision of animproved construction of valve of the above stated character which willminimize the possibility of the valve holding-open or retaining an openposition when it should be in a seated position and to reduce to aminimum vibration and noise due to the shock of the valve lifter or itstappet striking the valve for the opening thereof, consequentlymaterially increasing the life of the valve and providing for betterengine performance and permits less clearance to be employed between thevalve tappet and the stem of the valve for the compensation of valveexpansion.

With these and other objects in view as will become more apparent as thedescription proceeds, the invention consists in certain novel featuresof construction, combination and arrangement of parts as will behereinafter more fully described and claimed.

For a complete understanding of my invention, reference is to be had tothe following description and accompanying drawing. in which Figure 1 isa side elevation illustrating an engine valve constructed in accordancewith my invention.

Figure 2 is a fragmentary vertical sectional view through Figure 1showing the construction of the stem of the valve made in accordancewith the present invention.

Referring in detail to the drawing, the numeral I indicates in entiretythe valve which consists of the head 6 and stem 1. The stem is oftelescopic construction consisting of the sections A and B. The sectionA is provided with a socket 8 opening outwardly of the lower end of thesection A and is partly screw threaded to permit threading ,therein amember 8 forming a part of the section B of the valve stem. The overalllength of the member 9 is much less than the depth of the socket I sothat a member ill of the section B may be slidably received within thesocket 8 as well as the cushioning spring II. The cushioning spring isattached to the members 9 and III, as shown at if. The form ofattachment of the spring to said members 9 and Ill may be varied. suchas welding or fasteners of some kind passed through openings in thespring I l and threaded into the members 8 and Ill. During all positionsof the valve the spring II is confined in the recess I and is protectedby the section A of the valve stem while the section B protrudes fromthe recess to be contacted by the usual tappet of the valve lifter of anensine.

It is always necessary to compensate for expansion of the valve by heatin an engine by providing a certain amount of clearance between thetappet of the valve lifter and the section B of the stem I. However,when the construction as shown in the drawing is employed less clearancewill be necessary to compensate for this expansion of the valve thanwhen the stem of the valve is of a conventional construction or all inone piece due to the fact that when the valve 5 expands from heat andthe section B of the stem being engaged by the lifter, the spring I Imay compress which will allow the valve head 6 to properly engage itsseat when the cam operating the valve lifter is in its lowermostposition or the low face of the cam is in contact with the section B ofthe stem.

Also, it will be noted that when the valve lifter is moved upwardly tounseat the valve, its movement is very sudden and due to the clearancebee tween the tappet and the section B of the stem the tappet willstrike said section B with considerable force and the spring ii acts toabsorb the shock created by said force thereby prolonging the life ofthe valve and reducing noise and vibration to a minimum.

While the spring I i is shown of substantially 8 shape, other cushioningsprings of different shapes may be employed.

While I have shown' and described the preferred embodiment of myinvention, it will be understood that minor changes in construction,combination and arrangement of parts may be made without departing fromthe spirit and scope of the invention as claimed.

Having thus described my invention, what I claim is: y

1. In a valve for internal combustion engines, a valve head, a stemintegral with said head and including telescopic sections and one oisaid sections adapted'to be engaged and disengaged by a tappet of avalve lifter, cushioning means arranged between the telescopic sections,and means for adjustably securing said one section and said cushioningmeans to the other of said sections.

2. In a valve for internal combustion engines, a valve head, a stemintegral with said head and including telescopic sections and one ofsaid sections adapted to be engaged and disengaged by a tappet of avalve lifter, a cushion spring engaged by the telescopic sections, andmeans for adjustably securing said one section and said cushion springto the other of said sections.

3. In a valve for internal combustion engines, a

' valve head, a stem integral with. said head and 2 I tions adapted tobe engaged and disengaged by a tappet of a valve litter, and a cushionspring connecting the telescopic sections and housed by one of saidsections at all times.

4. In a valve, a valve head, a stem integral with said head andincluding a rigid section having a socket opening outwardly through itsi'ree end and a second section composed of a pair of members one securedwithin the socket of the valve stem against movement and the otherslidably received in the'socket and protruding therefrom to be ensagedby a tappet of a valve litter, and a substantially a-shaped springconnecting said members and confined within the socket.

ADAM PASTORE.

